Forum:Master Xehanort Plan?
I believe Master Xehanort has like some diabolical plan going but we're not given trailers that show this. Mainly trailers that try to avoid Master Xehanort having any association with the darkness. Well if you think about it... Master Xehanort may have at one point tricked Terra into becoming his Apprentice by swaying him towards darkness (like Xehanort's Heartless did to Riku). Once Terra became his Apprentice, he technically lost his heart and his heart manifested into the Lingering Sentiment that is currently the "good" Terra. The Apprentice is possessed by Xehanort but at the same time, Xehanort continues to be himself, so that he can retain his own power of the light and Kingdom Hearts while still being able to preform dark acts or use the powers of darkness. Perhaps he is even using his powers of the light to trick Kingdom Hearts so that he can control it eventually by using his Apprentice and that would explain his sick obsession with it while as his Heartless and Xemnas. Xehanort's Heartless basically would have been doing the same thing, by using Riku to take over Kingdom Hearts. However, his Apprentice might have gone crazy over darkness seeing as it has no heart and began to become a threat to Xehanort, although he's acting as it's ally. He then probably attempts to persuade Terra into destroying it which would probably destroy Terra as well (at least in Xehanort's mind) and then he would find a new Apprentice to use which he may have attempted to start using Ven as his next Apprentice. Probably during the course of Birth by Sleep, Terra will become whole again but hold a piece of Xehanort's heart with in him (or Xehanort's entire heart if he is defeated in the game) and he tries to leave it all behind eventually causing changes to his body which results in him forgetting who he is and he becomes the new Xehanort. It's probable that Xehanort's heart started to take control of Terra/Xehanort and forced him to study the heart and then he eventually would become the evil possessed Xehanort we know now. Eventually Terra becomes a Heartless and Nobody, and the Heartless probably is the essence of Xehanort while Xemnas is the essence of Terra.
Pretty good theory?
It's just made up from what is available and I hope it sounds good. I'm also sorry to have no talk bubble but I didn't want to forget this so I typed it as soon as I could. I will edit soon.